Load-Sensing Hydraulic Pressure Regulation for Variable Standby Flow

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing hydraulic systems with Load Sensing technology face inefficiencies in pump operation, particularly when lower flow rates are required, and high standby consumption and dissipation, limiting flexibility and optimization.

Innovation Solution

A hydraulic system incorporating a 2-position 3-way proportional valve controlled by proportional pressure reducing valves, allowing for management of the pressure jump between supply and Load Sensing pressures, enabling adjustable flow rates and reduced standby consumption based on operational conditions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If a fixed standby pressure is imposed via dosing niches of the slider, then a fixed flow rate is imposed independent of the LS pressure, but the pump standby consumption and dissipation increase

Engineering Contradiction:
Improveflow rate controlVSAvoidpump standby consumption
Core Design Contradiction:
ProductivityVSLoss of energy

Solution Approach 1:

The patent applies dynamics by making the standby pressure variable rather than fixed. The dosing niches of the slider are configured to impose a standby pressure that varies according to the Load Sensing (LS) pressure level. When LS pressure is high, the standby pressure is reduced, and when LS pressure is low, the standby pressure is increased, allowing the pump to operate more efficiently across different operating conditions while maintaining proper flow control.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The invention changes the parameter of standby pressure from a fixed value to a variable value that depends on the LS pressure. By configuring the dosing niches to create a pressure relationship where standby pressure = f(LS pressure), the system adapts its pressure parameters dynamically, reducing energy loss while maintaining flow control independence from LS pressure variations.

Inventive Principle:
Principle #35Parameter changes

2Loss of energy

If the pump sends only the flow rate necessary to generate the pressure jump imposed by the flow rate regulator, then energy consumption is reduced, but the system loses flexibility in managing pressure jumps under different operating conditions

Engineering Contradiction:
Improvepump energy consumptionVSAvoidpressure jump management flexibility
Core Design Contradiction:
Loss of energyVSAdaptability or versatility

Solution Approach 1:

The system dynamically adjusts the pressure jump management based on operating conditions. The dosing niches of the slider automatically modulate the standby pressure according to the LS pressure level, allowing the pump to maintain optimal energy consumption while the system adapts to different operating conditions. This dynamic adjustment provides flexibility without requiring active pump control modifications.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The dosing niches of the slider perform a self-service function by automatically regulating the standby pressure based on the LS pressure. The system uses its own operational parameters (LS pressure) to automatically adjust the pressure jump management, eliminating the need for external control mechanisms while maintaining both energy efficiency and operational flexibility.

Inventive Principle:
Principle #25Self-service

3Device complexity

If traditional Load Sensing systems use a fixed compensator, then the system structure is simple, but the system lacks adjustment variables to optimize different conditions of use

Engineering Contradiction:
Improvesystem structureVSAvoidregulation flexibility
Core Design Contradiction:
Device complexityVSAdaptability or versatility

Solution Approach 1:

The invention introduces local quality by configuring the dosing niches of the slider with specific geometric characteristics that create a variable standby pressure effect. Instead of using a uniform fixed compensator, the dosing niches are designed with local variations in their structure (dimensions, positions, orientations) that enable them to impose different standby pressure levels depending on the LS pressure, thereby adding regulation flexibility to the otherwise simple Load Sensing structure.

Inventive Principle:
Principle #3Local quality

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This solution enhances regulation flexibility, optimizes energy consumption, and allows for variable torque control, improving system efficiency and sensitivity by managing pressure jumps and standby values dynamically.

Implementation Method 1

two proportional pressure reducing valves (5, 6) arranged to provide a reduced pressure signal (pr1, pr2) to the proportional valve (4)

Methodology Applied
Scientific EffectPressure reduction: Pressure Drop

Implementation Method 2

a 2-position 3-way proportional valve (4) supplied by the supply channel (2) and connected to the flow rate regulator (11) of the pump (12) via a supply channel (31) for a conditioned pressure signal (LSc)

Methodology Applied
Scientific EffectHydraulic flow control: Hydraulic Press

Implementation Method 3

a channel (30) configured so as to receive from the sections of the valve distributor a Load Sensing signal, to which a respective Load Sensing LS pressure corresponds

Methodology Applied
Scientific EffectHydraulic pressure transmission: Pascal's Law

Data Source

PatentEP3667103B1Load sensing type hydraulic system with hydraulic regulating device
Publication Date: 2023.06.21 WALVOIL
  • EP3667103B1 patent drawingFigure 1
  • EP3667103B1 patent drawingFigure 2
  • EP3667103B1 patent drawingFigure 3a

AI summary

A hydraulic system comprises a valve distributor comprising one or more sections connectable to respective uses, a supply apparatus comprising a pump and a supply channel, a discharge channel connected to a low-pressure tank, a use signal channel coming from the section of the valve distributor and further comprises a hydraulic regulating device connected via said channels which includes a 2-position 3-way proportional valve configured so as to provide operative fluid at a conditioned pressure, different with respect to the pressure that is characteristic of the operative condition of use, to the supply apparatus and at least one proportional pressure reducing valve.